DCS system card configuration issue
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Discussion: 1. A certain device uses a TPS (GUS/HPM) control system. If there are 95 analog input points AI, all of which transmit high-level signals of 4-20mA, with 37 of these being control loops – assuming each of them is a single-loop control system – and the remainder being indicator loops, then for the control loops redundancy in terms of card configurations must be taken into account, without considering any margin. If you were to design this system, how many HLAI cards would be required at minimum? The HLAI cards are calculated based on 16 channels per card.
If each HLAI card has 16 channels, all of which are high-level 4-20mA input signals: For 95 analog input points AI, each HLAI card can handle 16 signals; therefore, 95 AI points require at least 95 / 16 = 5.9375 cards. In other words, at least 6 HLAI cards are needed to achieve a non-redundant configuration. However, since redundancy needs to be implemented for the 37 control loops, assuming a single-redundancy configuration is used here (i.e., each control loop has two input points), these 37 loops will actually require an additional 37 AI points. So the total number of AI points required will be 95 + 37 = 132 AI points. The number of HLAI cards required for 132 AI points is 132 / 16 = 8.25; therefore, at least 9 HLAI cards are needed to meet the requirements of all analog input points (including those for redundancy). .
1. Control circuit: 37/16=2……5; with redundancy, 3×2=6. 2. Indication circuit: (95-37)/16=3……10. 3. At least 6+4=10 HLAI cards are required.
The interlocking measurement points are equipped with redundant cards, and the AO cards also have redundancy. Additionally, you can choose Hart card holders for all 4-20ma cards. Cards with Hart will be expensive.
(95+37)/16=8.25, so 9 are needed; how is this turned into a math problem?:L
The redundant cards must be 6 in groups of 3, with 11 extra points. If margin is not considered, higher specifications can be assigned to the non-redundant nodes, for a total of 9 cards, with one empty slot remaining for the non-redundant cards. If margins are taken into account, there are 3 redundant cards for 6 cards, plus 4 non-redundant cards, for a total of 10 cards. It is recommended to use the latter mode; after all, if a channel gets damaged after 4 to 5 years and an additional card has to be installed, the cost will not be the same.
10 are configured for redundancy, 6 for non-redundancy, and 4 for regular use, meeting the actual configuration requirements. If it’s a pure math problem, it’s 9 yuan.